Reality Check: Has a city the size of Newcastle come to the UK?

The claim: "Last year alone a city the size of Newcastle came to this country net. The gross figure is roughly the cities of Liverpool and Aberdeen put together"

Reality Check verdict: Mr Nuttall is about right on the net figure but the gross figure is lower than he says, according to the best estimates we have.

Launching his party's general election campaign on Friday, UKIP leader Paul Nuttall said "last year alone a city the size of Newcastle came to this country net".

When he talks about the net figure, he means the number of people who have come to live in the UK planning to stay for at least a year, minus those who have left for at least a year.

The figures for the whole of 2016 will not be released until 25 May, but we know around 596,000 people came to the UK in the year to the end of September 2016 while about 323,000 people left the country, according to the latest set of numbers from the Office for National Statistics (ONS), giving a net figure of 273,000.

According to the most recent set of official figures, the population of Newcastle upon Tyne is 292,883, so these two figures are similar.

But Mr Nuttall's second claim is more questionable. He said the number of people moving to the UK was: "roughly the cities of Liverpool and Aberdeen put together".

Official estimates suggest that it is lower than that.

Liverpool's population is 478,580 according to the latest figures from the Office for National Statistics (ONS), while Aberdeen's is 230,350.

The combined total is 708,930, so there is an clear difference between that and the gross immigration figure of 596,000.

These migration numbers are estimates based on the international passenger survey.

Hundreds of thousands of people a year are interviewed at airports, sea ports and the Channel Tunnel and asked if they are planning either to enter the UK to stay for at least a year or leave for at least a year, which would make them long-term migrants.

About 4,000 people interviewed a year are long-term migrants. The rest are passengers travelling for shorter periods, such as tourists and business travellers.

From speaking to these 4,000 people, the ONS extrapolates the total numbers of people entering or leaving the UK for at least a year.

Lots of the UK's most important statistics come from surveys like this.

It means the figures are estimates and there is a margin of error in them.

The ONS is 95% confident that net migration is no more than 41,000 higher or lower than 273,000. Mr Nuttall's Newcastle comparison falls comfortably within this, and is therefore a reasonable comparison.

However, on the gross figure, the ONS is 95% confident that it is no more than 34,000 higher or lower than 596,000.

Therefore, it is unlikely the number is as high as 708,930, the population of Liverpool and Aberdeen put together.

UKIP has in the past suggested that the official migration statistics are an underestimate.

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